My daughter's problem with her ninth-grade math teacher sneaked up on me. She began to speak of him as if he were several phyla below a banana slug, but she was 15 years old at the time, and that is an intolerant age.

She said the teacher was hard to understand. She said he praised the boys and belittled the girls, many of whom dropped the course. She said he seemed impatient with questions, and was too young and inexperienced to realize how much this was hurting his students. I ignored her until the situation hit that most sensitive of parental nerves -- her math grade began to drop.

There are few occasions as unsettling as your child falling out with a teacher, and that goes double for high school, where every report card seems to count. I had the usual panic response: She is going to blow this class and get a bad grade and see her GPA plummet and never get into med school.

What was I supposed to do? That may be what bothers parents most -- the feeling of helplessness when communication between student and teacher has broken down -- and the system does not seem to have a procedure for dealing with it.

Much of this is our fault as parents. We have more influence than we realize and can find ways to work through these crises -- if we do not lose our tempers. But let's not be so introspective that we don't also blame the widespread clumsiness of teachers and principals who deal with parents.

I have been looking closely at how Washington area schools handle teachers who are not doing their jobs well, and the people who complain about them. We dazed and confused parents are often treated like coyotes who have wandered into the educators' back yard. The message is: You don't belong here. We are usually not yelled at or sprayed with the water hose or shot, but the reception in the principal's office can be chilly, and we rarely get the information or action we seek.

I asked some experienced parents what they do about this. They endorse the view of the best principals and teachers: Whatever the resistance, do your best to talk the problem out with the people at the school. Dick and Karen Reed, who have had two daughters in Fairfax County schools, say a face-to-face meeting with the teacher and the relevant administrator is best. You have to make sure the meeting does not end until the problem is defined and a solution agreed upon. Then, and this is the part that I was too lazy ever to try, the Reeds compose a summary of the discussion and the agreement and send it to the educators. "I don't accept corrections or edits from them," Dick Reed says. "I do offer to meet again if they wish to change something."

John Hoven, who had a son and a daughter go through Montgomery County schools, recommends getting ahead of potential problems by volunteering in your child's classroom and making friends with the teacher. As for grades, he says, don't complain about them before high school because they don't matter, and don't complain about them in high school because your kid probably deserves them. Instead, Hoven says, tell your elementary school child it is only what she learns that matters, "and tell your high school child that grades have become important now, so let me show you how you can get your work done and still have time for fun."

I think gross injustices, however, require a confrontation, if only to build a record against a bad teacher and show your kid that bullies must be resisted. Cecilia Plante of Montgomery County says her son received an F on a year-long project from a sixth-grade teacher with a well-known mean streak. Their son had done all that the written instructions asked for, and more, but had failed to complete part of a page in the correct form under oral instructions the teacher had uttered once early in the year. It was hard for Plante to believe that a teacher would refuse to give any credit for a year's work because of that small mistake, but Plante checked the facts, and met with the assistant principal. He confirmed what her son had told her. Plante and her husband refused to leave his office until he did something about it, and the grade was changed.

That is an extreme example of a teacher who is off track. The situation is usually quite different. Parents cannot always be sure that their children are not exaggerating or just making things up. Sometimes there are simple misunderstandings. In many cases, it is best to let your kid handle it.

Take, for instance, my daughter's math teacher. I did nothing about him. My wife had written a letter to our son's high school principal about a struggling Spanish teacher a few years before, and that had prompted no action. We figured that this case was also hopeless. My daughter endorsed our decision to butt out. She found a way to survive. Her subsequent math teachers were better, restoring her interest in the subject and eventually making her the only family member ever to take math electives in college.

And, as sometimes happens, her clumsy ninth-grade teacher improved. He turned out to be a very conscientious young man. He asked his students to critique him at the end of each year, and he took the comments to heart. My daughter's friends who had him later were surprised that she -- and I -- nursed such a grudge against him, and told us, rightly, to grow up.

Jay Mathews can be reached at mathewsj@washpost.com.